Planar Chromatography

Abstract

GENERAL CONSIDERATIONSHistory, Books, Reviews, and Student Experiments. The discovery of TLC by Nikolai Izmailov and Maria Schreiber in 1938 was reviewed (A1). The first TLC book arranged by discipline contained chapters covering applications in bacteriology, plant sciences, parasitology, entomology, clinical chemistry, environmental analysis, food analysis, forensic toxicology, pharmaceutical analysis, veterinary toxicology, and analysis of skin secretions in vertebrates (A2). A book on TLC in German contained a random assortment of chapters on techniques and applications, including uses in a clinical laboratory, properties of different layers, determination of the pesticide propham, optimization of mobile phases, video densitometry, determination of PAHs in water, determination of water solubility of higher fatty acids, visualizing reagents for higher fatty acids, pharmaceutical analysis, on-line coupling of AMD and HPLC for determination of plant protection agents in water, and enzymic detection of pollutants (A3). A TLC atlas for plant drug analysis was published (A4). The fourth edition of Thin Layer Chromatography-Techniques and Applications by B. Fried and J. Sherma is in production and will be published by Marcel Dekker, Inc. in late 1998 or early 1999.Review articles were published on the following topics: instruments and techniques (A5), determination of organic compounds (A6), food analysis (A7), environmental analysis (A8), and general progress and development (A9). Other pertinent reviews are cited in the sections below.

Densitometric HPTLC and HPLC analysis of phenolic acids fromAquilegia vulgaris

“…According to the literature, multiple gradient development gives better results [21][22][23][24][25], so we decided to use this method for separation of the phenolic acids from the A. vulgaris extract. In our investigation the best resolution was obtained by using a mixture of heptane, dichloromethane, diisopropyl ether, formic acid, and water in the five-step gradient programme presented in Table 1.…”

Use of Nonionic Tween-80 Surfactant Mobile Phase in Thin Layer Chromatography of Heavy Metal Cations

“…Ion chromatography using surfactants is now the most accepted technique for analyzing inorganic cations, since it offers considerable advantages over classical methods in term of speed, precision and accuracy. This method has been used in (Mohammad et al, 1996, "a", "b" andSherma 1998), and the mobile phases used in inorganic solvents; or aqueous solution of acids, bases and salts. Although organic solvents like benzene, chloroform, acetone, methanol, acetonitrile, carbon tetrachloride, dioxane, acetic acid, phenols, cyclohexane and hexane are quickly removed from the sorbent layer after development, most of these are toxic to some extent.…”

Separation of cephalosporins on thin silica gel layers impregnated with transition metal ions and by reversed‐phase TLC

“…The literature on qualitative and quantitative TLC analysis of several antibiotics has been reviewed by Sherma (Sherma, 1990(Sherma, , 1992(Sherma, , 1994(Sherma, , 1998(Sherma, , 2000Sherma and Fried, 1982, 1984, 1986. Also a survey of TLC separation of those antibiotics which are in therapeutic use has been presented by Kreuzig (1996), which covers papers published after 1980.…”